Top PDF Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Chapter 8: Simulation of Repository Processes II: The Interaction of Granite and Synroc doped with Mixed Fission Products 8.1 Introduction - Previous Work 8.2 Mixed Fission Products.. 8.[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture·infilling and other secondary minerals, As an analogue for the behaviour o'f t[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

8.5 Conclusions The leach testing in deionised water of the Coles Bay Granite, Roxby Downs Granite and the Kambalda Granodiorite with Synroc doped with the mixed fission products under s[r]

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Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Radionuclide migration in plutonic rocks: implications for high level nuclear waste disposal

Interaction between the migrating ground waters and the rock has been influeneed by the presence offracture-infilling and other secondary minerals, As an analogue for the behaviour of th[r]

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Probabilistic modelling of calcium leaching in a tunnel for nuclear waste disposal

Probabilistic modelling of calcium leaching in a tunnel for nuclear waste disposal

The structure we consider is one of these cells. For simplicity reasons and to ease the calculations, the considered geometry for the structure is very schematic: we simply consider a hollow cylinder, with an external radius of 8 m, and a thickness of 1 m. The disposal cell can reach a length of several hundreds meters. Figure 1 schematically represents the problem that we model. A tunnel for the waste packages disposal is dug in the soil, and a concrete wall protects the environment from the waste containers contained within the tunnel. The site water contained in the geological formation exposes the concrete tunnel to the risk of leaching. Even though this kind of degradation is very slow, it is to be considered as the required lifespan for such structures is several hundreds of thousands years.
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Analysis of the quality of environmental disclosures made by Australian resources sector companies

Analysis of the quality of environmental disclosures made by Australian resources sector companies

A number of theories seek to explain the motivation for providing environmental disclosures. For example, legitimacy theorists view disclosures as a tool for obtaining, maintaining and/or repairing legitimacy (Deegan, 2002; O’Donovan, 2002). This theory largely adopts a broad notion that managers do not provide a comprehensive account of the environmental externalities of their organisational operations. Instead, they provide disclosures so that their company is perceived as environmentally responsible while bringing little change in improving their environmental footprint. At a more refined level, the NRBT upholds the notion of environmental pragmatism and promotes the idea of ‘win-win’ situations through the adoption of environmental management (Prasad and Elmes, 2005, p. 848). The theory assumes that if a company adopts environmental management systems to reduce its operational impact and provides disclosures to that effect, it would be able to gain competitive advantage in terms of surviving and thriving into the future (Hart, 1995). While the adoption of environmental management provides a reasonable solution to reducing a number of environmental impacts, it does not go to the root of environmental problems resulting from escalating consumerism. Instead, concerns are expressed that the rising popularity of environmental management, because of its ability to provide appealing solutions, essentially marginalises the other radical eco-centric viewers and proves them to be absurd for denouncing growth and development (Prasad and Elmes, 2005). In one way or another, both these theories promote the view that disclosures have an impression-building
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Potential migration of buoyant LNAPL from Intermediate Level Waste (ILW) emplaced in a geological disposal facility (GDF) for UK radioactive waste

Potential migration of buoyant LNAPL from Intermediate Level Waste (ILW) emplaced in a geological disposal facility (GDF) for UK radioactive waste

Consistent with the overall ambition to better understand the nature of any source term of LNAPL emanating from a GDF, the aim of the numerical modelling is to first understand the potential for LNAPL to migrate from the waste package in which it (or its precursor material) is initially present (Fig. 1), and then to determine likely timescales for migration through the overlying backfill before the LNAPL is able to enter the host rock. This is consistent with the “ multi-barrier ” approach to the engineering design of a GDF and allows the efficacy of each of the engineered barrier system to be investigated. The models comprise a single waste package in isolation; no interference from LNAPLs released from neighbouring packages is consid- ered. Scenarios considered the waste package to either be: intact (as emplaced); contain cracks in the grout; or include an annular failure in the waste package (e.g. due to corrosion at a weld) and/or cracks in the encapsulant. In the latter case, the annular failure was assumed to be located at the bottom of the waste package to maximise the pressure gradient through the waste package (given the boundary conditions that have been chosen; see Section 3.4.2) and therefore maximise the potential for migration of LNAPL out of the package. Since the rate of LNAPL generation from precursor material is uncertain, the total potential package LNAPL inventory is assumed to be available at the start of the modelled period.
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Waste Recycling: Utilization of canteen(kitchen) waste and garden waste in vermicomposting

Waste Recycling: Utilization of canteen(kitchen) waste and garden waste in vermicomposting

Aristotle was ahead of our times by two and half of millennia. It defines the exact potential for waste reduction, fertilizer production, as well as solid waste management of possible uses for the future. Vermicomposting is the process of producing organic fertilizer or the vermicompost from bio-degradable materials by using species of earthworms. Composting with worms avoids the needless disposal of vegetative food wastes and enjoys the benefits of high quality compost [10]. The worms are capable to convert waste into the superior quality of the fertilizer. They break down organic matter and convert organic matter into the vermicast having the good quality of manure, and this manure used as a soil fertilizer. Now a day the waste disposal of organic waste is an important point to reduce the cost of the waste disposal have escalated and environmental regulation and their disposal have become restrictive, the vermicomposting in which garden waste, kitchen waste with addition of cow dung are composted by using earthworms, and the composted waste used as soil conditioner or fertilizer, Vermiculture and Vermicomposting [15]. The basic principle of vermicomposting is an alternative to thermophilic composting is use certain epigic species of earthworms to break down organic wastes and converted into vermicompost that can be used for the agriculture for soil improvement as bedding media. Many of the organic wastes produced by agriculture, farms, and modern industrial technology cause odor problems or can result in the pollution of groundwater. Early research in the Rothamsted program suggested that these problems could be alleviated by the use of earthworms, particularly Eisenia fetida (Savigny) and other epigeic species such as Eisenia andrei (Bouché), Dendrobaena veneta (Rosa), Eudrilus eugeniae (Kinberg), and Perionyx excavatus (Perrier), to accelerate the aerobic decomposition of organic wastes, thereby minimizing odors and pollution and producing a considerable potential profit from the sale of earthworms and also of the vermicompost for use as a plant growth medium. The vermicomposting process completed in 49 days or up to the 6 month below 25 _C[21].the moisture content for vermicopost is 80%. Some popular composting Methods are:
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Effect of the Heating Rate on Residual Thermo-hydro-mechanical  Properties of a High-strength Concrete in the Context of Nuclear Waste  Storage (H381)

Effect of the Heating Rate on Residual Thermo-hydro-mechanical Properties of a High-strength Concrete in the Context of Nuclear Waste Storage (H381)

Examples of mass loss curves are shown in Fig. 2. These curves proved that the mass loss plateau was reached for each thermal loading. Through this, we checked that there was no significant amount of water unremoved for each temperature level. Slight differences, observed mainly at 150°C, are probably related to discrepancies in the initial water content of the specimens. Mass loss values evolution obtained after thermal treatments are plotted in Figure 3. This parameter evolves linearly with the temperature. On average, at 110, 150, 200 et 250°C, mass loss values were respectively, 11.5 ± 0.1 %, 12.4 ± 0.4 %, 13.0 ± 0.2 % and 13.8 ± 0.3 %. Taking into acount experimental uncertainties, we assumed that the mass loss did not evolve with the heating rate. This result confirms that the intensity of dehydration is only controled by temperature level and that there is no artefact effect due to the heating rate.
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The effect of organic retarders on grout thickening and setting during deep borehole disposal of high-level radioactive waste

The effect of organic retarders on grout thickening and setting during deep borehole disposal of high-level radioactive waste

Deep borehole disposal (DBD) is being increasingly seen as a viable and potentially superior alternative to comparatively shallow mined repository concepts for disposal of some high-level radioactive wastes. We report here details of proof-of-concept investigations into the use of cementitious grouts as sealing/ support matrices for use in low temperature DBD scenarios. Using the cementitious grout to fill annular space within the disposal zone will not only support waste packages during placement, but will also provide a low permeability layer around them which will ultimately enhance the safety case for DBD. Grouts based on Class G oil well cement are being developed. The use of retarders to delay the accel- erated onset of thickening and setting (caused by the high temperature and pressure in the borehole) is being investigated experimentally. Sodium gluconate and a polycarboxylate additive each provide suf- ficient retardation over the range 90e140 ! C in order to be considered for this application. Phosphonate
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THE FACTORS THAT AFFECTING ON SOLID WASTE GENERATION IN ZALINGY TOWN – CENTRAL DARFUR STATE – SUDAN 2015

THE FACTORS THAT AFFECTING ON SOLID WASTE GENERATION IN ZALINGY TOWN – CENTRAL DARFUR STATE – SUDAN 2015

also the study revealed that there are decrease in personal income where as 35% of people their monthly income is just 500 Sudanese pound, research found that 96.6% of study population not pay fees for solid waste management and 93% of people said that there are no strength of solid waste management policies, laws and enforcement. Finally according to results the study recommended that: establish effective solid waste management programme and support it with regulations and laws, increase environmental education or awareness about solid waste in study area and local governmental and none governmental sectors should be support solid waste management porgramme.
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Geothermobarometry of Askaoun Pluton in Ouzellarh Sirwa Promontory (Central Anti Atlas; Morocco)

Geothermobarometry of Askaoun Pluton in Ouzellarh Sirwa Promontory (Central Anti Atlas; Morocco)

rocks crystallized from A, P and C magma types. Based on his classification; biotites in anorogenic alkaline suites (field A) are mostly iron-rich, siliceous biotites (near annite), with an average FeO*/MgO ratio of 7.04; those in peraluminous (including S-type) suites (field P) are siderophyllitic in composition and have an average FeO*/ MgO ratio of 3.48; whereas biotites in calc-alkaline oro- genic suites (field C) are moderately enriched in Mg; with an average FeO*/MgO ratio of 1.76. It should be noted that the average FeO*/MgO ratio in biotite dou- bles from calc-alkaline through peraluminous to alkaline suites (FeO* = total Fe). Based on the biotite discrimina- tion diagram of the Abdel-Rahman (1994); these biotite of Askaoun granodiorite and MMEs are mostly located in calc-alkaline field (Figure 5). This corroborates with the geochemical features undertaken in the area using major and trace elements ([6], in reviews).
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Bio safety Knowledge, Waste Disposal Practices and
Identification of Parasites in Biomedical Wastes from
Healthcare Establishments in Lagos and Abuja, Nigeria

Bio safety Knowledge, Waste Disposal Practices and Identification of Parasites in Biomedical Wastes from Healthcare Establishments in Lagos and Abuja, Nigeria

Responses to questionnaires in this study also showed that HCE wastes in both Lagos (18.82 %) and Abuja (50.63%) were not treat- ed prior to final disposal. The disparity in these figures is likely to be a result of the understanding of the principles of bio safety and their putting them into practice by Lagos HCE workers relative to those in Abuja as earlier stated. It however shows that HCEs that failed to treat their wastes prior to final disposal do so in conform- ity with the general practice in Nigerian HCEs as reported by Ste- phen and Elijah [4]. It is established that the common practice in Nigeria is that the wastes are collected at a central open dumpsite and burnt periodically. Occasionally, the wastes are buried by cov- ering with a heap of soil without any prior treatment. Furthermore, human body parts such as placenta and amputated limbs are either disposed of with the general HCE wastes or given to the patients or their relatives to dispose of in their own way [5].
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Proposal for a Council Directive amending Directive 75/442/EEC on waste. Proposal for a Council Directive on hazardous waste. COM (88) 391 final, 5 August 1988

Proposal for a Council Directive amending Directive 75/442/EEC on waste. Proposal for a Council Directive on hazardous waste. COM (88) 391 final, 5 August 1988

- 2 - Whereas the tommission•s proposal takes as a base a high level of environmental protection with as much regard to the definition as to the disposal of hazardous waste; Whereas it i[r]

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The Community's research and development programme on radioactive waste management and storage  Shared cost action Annual progress report 1986

The Community's research and development programme on radioactive waste management and storage Shared cost action Annual progress report 1986

Progress of work and obtained results State of advancement The test disposal of high-level radioactive waste canisters in the Asse salt mine will be performed with a view to the planning[r]

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Characterisation of a high pH cement backfill for the geological disposal of nuclear waste : the Nirex Reference Vault Backfill

Characterisation of a high pH cement backfill for the geological disposal of nuclear waste : the Nirex Reference Vault Backfill

calcium silicate hydrate (C-S-H), AFt (ettringite) and AFm (mono- carboaluminate) phases, and possibly hydrotalcite if magnesium car- bonate is present in the limestone fl our or in the Portland cement (Holland and Tearle, 2003). At high temperatures (80 °C), the forma- tion of hydrogarnet-type phases was also predicted, according to ther- modynamic modelling (database not speci fi ed) performed by the same authors (Holland and Tearle, 2003), although more recent advances in cement chemistry and phase assemblage prediction models indicate that this may be less likely due to the high quantity of carbonate present in this cement formulation. Experimental X-ray di ff raction (XRD) per- formed on fresh (uncured) NRVB revealed that the main phase present was calcite, whereas for NRVB cured for 4 months and 3 years, the phase assemblage was dominated by portlandite (Felipe-Sotelo et al., 2012).
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Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

Ageing management program for the Spanish low and intermediate level waste disposal and spent fuel and high-level waste centralised storage facilities

From a structural standpoint the reinforced concrete vaults provides support to the confinement and handling systems. Being a robust structure with wall thicknesses of near 2 meters, it also gives protection against natural or man originated external risks, including resistance to earthquakes. Such a structure, with a careful design and material selection should not present any particular problem for a service life of some decades. Nevertheless, a number of strategic decisions on spent fuel management options should be made. A 60 years operational period has been assumed for the facility. However, the decision-making ‘processes for long-term management of spent fuel and high-level waste is subject to uncertainties. On the other hand, temperatures of 90 ◦ C in the bulk of some sections of the structure are not normal in general civil structures. For these reasons durability has to be an issue in designing those structures and an ageing management plan is a must.
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Canada's High-Level Nuclear Waste Disposal Concept: The Evaluation Process and a Review of Some Aspects of the Research Work

Canada's High-Level Nuclear Waste Disposal Concept: The Evaluation Process and a Review of Some Aspects of the Research Work

OCflce SAT - Subsurface Advisory Team (Environment Canada.) SRG - Scientific Review Group (FEARO) TAC - Technical AdvIsory Committee (AECI.) Figure 1: Evaluation of Canadian Nuclear Wast[r]

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High Heat Producing Volcano Plutonic Rocks of the Siner Area, Malani Igneous Suite, Western Rajasthan, India

High Heat Producing Volcano Plutonic Rocks of the Siner Area, Malani Igneous Suite, Western Rajasthan, India

The magmatic rocks of the MIS are spread out in an area about 55,000 km 2 in the Indian subcontinent around To- sham in Haryana, Jhunjhunu, Siwana, Jalore, Barmer, Pali, Jaisalmer in Rajasthan and Kirana Hill, Nagar Pakar in Pakistan. The Siner area dominantly consists of felsic volcano-plutonic rocks in the southwestern part of the Siwana Ring Complex occur in the Siner area (Figure 1). Volcano-plutonic associations of the MIS belongs to three different phase. First phase is initiated by flow of minor basic volcanic rocks followed by major felsic flows; second phase is represented by intrusive phase. The dyke rock represents the third phase and they have
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The Geochronology of the Plutonic and Metamorphic Rocks of New Zealand

The Geochronology of the Plutonic and Metamorphic Rocks of New Zealand

Biotite also occurs as large poikolitic grains including pyroxene, magnetite, and hornblende; it also is developed around the edges of pyroxene, Magnetite is associated with pyroxene int[r]

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